CLUTCHING at SPRINGS

[Wheelman-111]

Greetings:

With the recent most generous but failed attempt by ScooterWerx to provide me with Monster clutch springs, my limited brain capacity has turned to the question of clutch engagement speed.

One way to affect the clutch behavior is to change the stiffness of those three springs inside the bell. If I want the clutch to engage at a higher speed, simply install stronger springs. They fight/balance the centrifugal forces generated by the three clutch shoes and determine the RPM at which the clutch starts to... uhh, you know - Clutch. Stronger springs needs more revs before the shoes start their outward swing. But is there another way?

An Old snowmobile trick was to drill material out from the kidney-shaped clutch weights, making them lighter. Like small-displacement scooters, modified sled engines were pretty gutless at low revs, so this put the engine into its powerband before being asked to supply propulsion. It's a bit more of a PITA on a scooter, because it requires disassembly of that pesky 39mm nut each time. On the other hand, the cast aluminum drills a whole lot easier than the old steel snowmobiles' steel counterweights.

Now you wouldn't want to remove too much material, lest it need to wind out to stratospheric levels before engagement. But I think it'll work. I have nifty HF scale to balance things pretty closely. Has anyone done it? If so: How many grams (or what percentage) should I shave to start?

[scooterwerx]

this seems like a great idea, the malossi delta clutch has different weights that clip in so you can alter their weights to suit your engines characteristics, this is just more permanent!

[Wheelman-111]

Greetings:

How heavy are those Malossi weights? I don't suppose you know the weight of the clutch "shoes", too?

Knowing spring stiffness, length of the pivoting arm, radius of pivot points, balance point and gram mass of the shoes would allow me to severely miscalculate how much material to remove. I wish I'd paid more attention in Physics class but there was this girl - Beverly - mmmmmm!

OK I'm back! I think I'll just start hackin' and stop when it's sweet.

[scooterwerx]

if you wanted adjustability, you could drill and tap the holes so weight could be re-added with small set screws, properly loctited and secured, of course!
then if you went too far, you can regress to said sweet spot!

[Wheelman-111]

Greetings:

Wise Werx Waxes Academic:

malossi delta clutch has different weights that clip in so you can alter their weights to suit your engines characteristics

I'd still like a ballpark on those weights. I know they won't tell me a specific thing - it's a whole different clutch after all - but maybe give me at least an Order Of Magnitude before I start drilling, filing, and filling. If you have pics or Tech drawings of Malossi's system, we could all learn to tune our stock clutches just like the Big(ger) Scooterboys.

I really like your setscrew idea too. Have Cheap HF Taps and gram scale. Other than to weigh the clutch shoes the first time, I won't have to fumble with that 39mm Nut every time. THAT one goes on with LocTite RED next time. Then weigh the bolts that would replace lost Alu material with denser steel, and one can imagine the fun we can have.

So are the Malossi weights like 5g, 10g, 15g and so on? This'll be fun! I have a used clutch assembly coming. If I (m)uck it up, I can go back stock.

[noiseguy]

Drilling the pads to increase engagement is a pretty common trick on peds and scoots. I have no guidance on amount, but make sure you have a scale around to track how much you remove and keep it even between pads.

[Wheelman-111]

Greetings:

Helpful NoiseGuy suggests:

make sure you have a scale around to track how much you remove and keep it even between pads

.

That's the plan. Depending on the gram weight of the 3 shoes, maybe start with 5%? I'll use a hole size that I can tap with a common-size of screw, fill back in with said screw if I find I've removed too much...